Question

E. coli uses which of the following enzymes to regulate membrane fluidity? (hint: E. coli has to survive in cold weather)

A. desaturase
B. gangliosidase
C. fatty acid convertase
D. glucose-6-phosphatase

Answer 1

E. coli uses the enzyme desaturase to regulate its membrane fluidity, adapting to cold temperatures by increasing the unsaturation of lipids in its cell membrane.

Step-by-step explanation:

E. coli uses the enzyme desaturase to regulate membrane fluidity, particularly when the bacterium needs to survive in cold weather. This enzyme alters the lipid composition of the cell membrane by introducing double bonds into the saturated fatty acid tails, which increases the unsaturation of membrane lipids and, as a result, their fluidity at lower temperatures. A discovery of a mutant strain of E. coli that cannot regulate its membrane fluidity would likely have defects in the gene encoding the desaturase enzyme or its regulatory elements, providing insight into the mechanism of temperature adaptation.